Epson STYLUS Scan 2000 Service Manual page 20

EPSON Stylus Scan 2000
USB
Standard :based on
"Universal Serial Bus Specifications Revision 1.0"
"Universal Serial Bus Device Class Definition for
Printing Devices Version 1.0"
Bit rate :12Mbps (Full speed device)
Data encoding :NRZI
Adaptable connector :USB series B
Suggested cable length :2 meters
Table 1-11. USB connector pin assignments and signals
Pin no. Signal name In/Out
1 VCC -
2 -Data bi-directional data
3 +Data bi-directional data, pull up to +3.3V via 1.5K
4 Ground -
Pin #2
Pin #3
Figure 1-8. USB Pins
Product Description
Description
Cable power, max. power consumption is
100mA
resistor
Cable ground
Pin #1
Pin #4
PREVENTING DATA TRANSFER TIME-OUTS
Generally, hosts abandon data transfer to peripherals when a peripheral is in
the busy state for dozens of seconds continuously. To prevent hosts from
entering this kind of time-out period, the printer slows down the data reception
rate to around several bytes per minute, even if the printer is in the busy state.
This slowdown starts when the remaining open buffer area decreases to
several hundred bytes. The Stylus Scan enters a continuous busy state if the
input buffer becomes full.
Interfaces
Revision A
20